200ml cider vinegar
200 ml water
10g salt (2.5tsp)
40g sugar (1/3 cup)
1tbsp black pepper
1tbsp mustard seeds
2 red onions
Cut the red onions lengthways and stuff into a masonry jar. Old mayo bottles work great for this.
Mix cider vinegar and water in saucepan.
Add sugar salt and mustard seeds and bring to boil.
Pour over and allow to cool.
Once cool refrigerate this will last about 3 weeks in the fridge.